In general, conventional guided munitions have movable fins which control their direction after launching of the guided munitions toward their targets. In some situations, such as under a wing of an aircraft prior to launch or during transportation, it is preferable to hold the fins rigidly in place. Such operation reduces wear, overstressing and the possibility of damage to the steering systems within the guided munitions while the guided munitions are carried by the aircraft for possible deployment or transported.
One conventional approach to holding the fins of guided munitions rigidly in place is to provide brakes which press against portions of the linkages to the fins. Electronic release circuits, which are typically separate from the guided munitions steering circuitry, then drive actuators to disengage or release the brakes at the time of deployment.
Another conventional approach to holding the fins of guided munitions rigidly in place involves the use of squibs (i.e., small explosive devices) or solenoids which are capable of quickly releasing hold of the fins. Here, bars or tabs initially engage the fins thus preventing unnecessary wear and possible damage to the control linkage prior to launch. Electronic release circuits, which are again separate from the guided munitions steering circuitry, then explode the squibs or activate the solenoids to disengage the bars or tabs and thus enabling the guidance system to freely control the direction of the fins.